The CityGML extension UtilityNetwork ADE defines concepts which allow for modelling different types of networks in the context of 3D city models, such as electricity, freshwater, wastewater, gas or telecommunication networks.

The CityGML UtilityNetwork ADE was originally developed in 2012 at the Institute for Geodesy and Geoinformation Science, Technische Universität Berlin. Within the OGC, a dedicated work package (WP 10) for integrating the UtilityNetwork ADE in CityGML 3.0 exists since 2014. Since 2015, the Chair of Geoinformatics at the Technical University of Munich intensely continued with the further development and improvement of the UtilityNetwork ADE. In October 2016, the SIG 3D and the OGC CityGML SWG started to organise joint workshops which aim at discussing and defining a harmonized version of the CityGML UtilityNetwork ADE to be included in CityGML 3.0. Please refer to the UtilityNetwork ADE workshop wiki for further information on these workshops.

The following papers provide detailed information on the CityGML UtilityNetwork ADE, use cases and projects that have applied the ADE:

• Becker, T., Nagel, C. & Kolbe, T. H., 2011: Integrated 3D Modeling of Multi-utility Networks and Their Interdependencies for Critical Infrastructure Analysis. Advances in 3D Geo-Information Sciences, Lecture Notes in Geoinformation and Cartography, Kolbe, T. H., König, G. & Nagel, C. (eds.), Springer, Berlin Heidelberg, 1-20: http://mediatum.ub.tum.de/doc/1145740/358854.pdf
• Becker, T., Nagel, C. & Kolbe, T. H., 2013: Semantic 3D Modeling of Multi-Utility Networks in Cities for Analysis and 3D Visualization. Progress and New Trends in 3D Geoinformation Sciences, Lecture Notes in Geoinformation and Cartography, Pouliot, J., Daniel, S., Hubert, F. & Zamyadi, A. (eds.), Springer, Berlin Heidelberg, 41-62: http://mediatum.ub.tum.de/doc/1145724/287720.pdf
• Kutzer, T. & Kolbe, T. H., 2016: Extending Semantic 3D City Models by Supply and Disposal Networks for Analysing the Urban Supply Situation. Publikationen der Deutschen Gesellschaft für Photogrammetrie, Fernerkundung und Geoinformation e.V., Volume 25, Kersten, T. P. (ed.), 36. Wissenschaftlich-Technische Jahrestagung der DGPF, June 7-9 in Bern, 382-394: http://www.dgpf.de/src/tagung/jt2016/proceedings/papers/36_DLT2016_Kutzner_Kolbe.pdf
• Hijazi, I., Kutzner, T. & Kolbe, T. H., 2017: Use Cases and their Requirements on the Semantic Modeling of 3D Supply and Disposal Networks. Publikationen der Deutschen Gesellschaft für Photogrammetrie, Fernerkundung und Geoinformation e.V., Volume 26, Kersten, T. P. (ed.), 37. Wissenschaftlich-Technische Jahrestagung der DGPF, March 8-10 in Wuerzburg, 288-301: http://www.dgpf.de/src/tagung/jt2017/proceedings/proceedings/papers/28_DGPF2017_Hijazi_et_al.pdf
• Kutzner, T., Hijazi, I. & Kolbe, T. H., 2018: Semantic Modelling of 3D Multi-utility Networks for Urban Analyses and Simulations – The CityGML Utility Network ADE. International Journal of 3-D Information Modeling (IJ3DIM), 7(2), 1-34: https://mediatum.ub.tum.de/doc/1475038/1475038.pdf
• Boates, I., Agugiaro, G., & Nichersu, A., 2018: Network Modelling and Semantic 3D City Models: Testing the Maturity of the Utility Network ADE for CityGML with a Water Network Test Case. ISPRS Annals of Photogrammetry, Remote Sensing and Spatial Information Science, IV-4, 13-20: https://doi.org/10.5194/isprs-annals-IV-4-13-2018
• den Duijn, X., Agugiaro, G. & Zlatanova, S., 2018: Modelling Below- and Above-Ground Utility Network Features with the CityGML Utility Network ADE: Experiences from Rotterdam. ISPRS Annals of Photogrammetry, Remote Sensing and Spatial Information Science, IV-4/W7, 43-50: https://doi.org/10.5194/isprs-annals-IV-4-W7-43-2018
• Ortega, S.; Wendel, J.; Santana, J.M.; Murshed, S.M.; Boates, I.; Trujillo, A.; Nichersu, A.; Suárez, J.P. Making the Invisible Visible—Strategies for Visualizing Underground Infrastructures in Immersive Environments. ISPRS Int. J. Geo-Inf. 2019, 8, 152: https://www.mdpi.com/2220-9964/8/3/152

The CityGML wiki provides information on the UtilityNetwork ADE as well. The resources available at the CityGML wiki refer to version 0.9.0 of the UtilityNetwork ADE. This version served as basis for the further development of the ADE and for the resources provided on this github repository.

The UML model of the CityGML UtilityNetwork ADE was created using the software Enterprise Architect.
The UML folder provides

• the Enterprise Architect file that defines the UML model and
• a PDF file that depicts the UML diagrams as well.

The XML Schema file of the UtilityNetwork ADE was derived automatically from the UML model using the software ShapeChange.
The XSD folder provides

• the derived XML Schema file and
• the derived code list dictionaries.

ShapeChange requires a configuration file to be able to derive the XML Schema file and code list dictionaries.
The ShapeChange folder contains

• the ShapeChange configuration file that was used for the derivation. For further information on how to use ShapeChange, please refer to http://shapechange.net/.

The CityGML UtilityNetwork ADE can be used with FME for writing network data in the CityGML format.
The FME folder provides

• an FME feature types definition file that needs to be imported into the FME workspace and
• a short tutorial that describes how to import the UtilityNetwork ADE feature types into an FME workspace.

There are currently two public data samples for the UtilityNetwork ADE. They are both created FME using the schema file contained in this repository:

1. Water Pipe Network in Nanaimo, British Columbia, Canada, created & maintained by Isaac Boates. More information can be found in a presentation at the 2017 CityGML UtilityNetwork ADE workshop and in the supplementary information

2. Sewer and Electrical Networks in Rotterdam, The Netherlands, created & maintained by Xander den Duijn. More information can be found in a presentation at the 2017 CityGML UtilityNetwork ADE workshop

OGC CityGML is an open data model and XML-based format for the storage and exchange of semantic 3D city models. It is an application schema for the Geography Markup Language version 3.1.1 (GML3), the extendible international standard for spatial data exchange issued by the Open Geospatial Consortium (OGC) and the ISO TC211. The aim of the development of CityGML is to reach a common definition of the basic entities, attributes, and relations of a 3D city model. By means of so-called Application Domain Extensions (ADEs) the core model of CityGML can be extended systematically by application-specific attributes and object types.

CityGML is an international OGC standard and can be used free of charge.